Machine vision systems extract large amounts of quantitative information from digitized images for use in process control, quality assurance, and other applications. The minimal apparatus required for a machine vision system is a computer and means to capture digitized images. More advanced machine vision systems incorporate special hardware to assist with the image processing because the images contain large amounts of data to be processed.
Most of the special processing hardware currently used for machine vision falls into two general categories: image-in/image-out processors and statistical processors.
The image-in/image-out types of processors typically receive a serial stream of pixel data and generate a serial stream of processed pixel data at the same rate. For example, the Sumitomo Metals model IP90MD25 spatial & logical filter module can perform 3.times.3 linear convolutions or binary logical filters receiving and generating serial pixel data at up to 25 mhz.
The statistical type processors typically receive a serial stream of pixel data and accumulate statistics internally which provide quantitative information about the image. For example, the Sumitomo Metals model IP90C01 histogram processor receives a serial stream of pixel data at up to 50 mhz and accumulates a 256-bucket histogram internally. Another example of a statistical type processor is the Sumitomo Metals model IP90C18 feature extraction processor, which may be used in conjunction with labeling processors and memories to accumulate statistics in an attached memory.